Description of Perkinsus beihaiensis n. sp., a new Perkinsus sp. Parasite in Oysters of Southern China

Abstract

Oysters were collected from coastal locations in China from 1999-2006 for parasite analyses by molecular, culture, and histological techniques. Polymerase chain reaction-based assays targeting the internal transcribed spacer (ITS) region of the ribosomal RNA gene complex were performed to detect the presence of Perkinsus species. Sequencing and phylogenetic analysis of amplified Perkinsus sp. DNAs indicated that a novel Perkinsus sp. infects Crassostrea hongkongensis, Crassostrea ariakensis, and other bivalve hosts from Fujian to Guangxi provinces in southern China. Prevalence of this Perkinsus sp. reaches as high as 60% in affected oyster populations. Analyses of nucleotide sequences of the rRNA ITS region and of large subunit rRNA and actin genes, consistently confirmed the genus affiliation of this Perkinsus sp., but distinguished it from currently accepted Perkinsus species. Parasite cell types, such as signet ring trophozoites of 2-8 microm diameter, were observed by histology, and application of both genus Perkinsus and Perkinsus species-specific in situ hybridization probes consistently labelled the same Perkinsus sp. cells in histological sections from infected oyster tissues. Combined phylogenetic and histological results support the identity of a new parasite species, Perkinsus beihaiensis n. sp.

Growth, mortality and susceptibility of oyster Crassostrea spp. to Perkinsus spp. infection during on growing in northeast Brazil

“…These results suggest that, when two susceptible host species are present, the progression of the two Perkinsus species can be modified in order to favor parasite progression in the most susceptible oyster species. Despite the knowledge that P. marinus causes outbreaks in C. virginica oysters from the East Coast of the USA (BURRESON & RAGONE-CALVO, 1996), P. marinus was not associated with mortality in other susceptible oyster species (Crassostrea and Saccostrea) (CÁCERES-MARTÍNEZ et al, 2010MOSS et al, 2008).…”

“…Moss et al (2008) noted some histopathological effects of P. beihaiensis in the digestive system (stomach, intestine and digestive gland) of Crassostrea hongkongensis from China, including cases of moribund oysters with heavy infections. Similar symptoms were observed in C. rhizophorae (SABRY et al, 2009) and C. gasar (QUEIROGA et al, 2015) from Brazil.…”

Comparison of diagnostic techniques to detect the clam pathogen Perkinsus olseni

“…P. marinus was the first species of the genus to be described and was reported as the causative agent of mortalities of Crassostrea virginica in the Gulf of Mexico (Mackin et al 1950). Since the synonymy between P. olseni and P. atlanticus (Goggin 1994, Robledo et al 1999a, Murrell et al 2002, Cremonte et al 2005) and between P. chesapeaki and P. andrewsi (Dungan et al 2002, Burreson et al 2005 has been described, the remaining species of the genus are P. qugwadi in Patinopecten yessoensis (Blackbourn et al 1998), Perkinsus mediterraneus in Ostrea edulis (Casas et al 2004), and P. honshuensis in Ruditapes philippinarum (Dungan et al 2006); recently, P. behaensis has been described in oysters from China (Moss et al 2008). However, Perkinsus spp.…”

Spatio-temporal patterns of perkinsosis in the Manila clam Ruditapes philippinarum from Arcachon Bay (SW France)

“…They have been associated with massive mortalities of commercially important mollusks including Crassostrea virginica in the USA (Andrews & Hewatt 1957) and Ruditapes decussatus in Spain and Portugal (Ruano & Cachola 1986, Azevedo 1989. The Perkinsus genus includes several species of molluscan parasites, including P. marinus from C. virginica (Mackin et al 1950, Burreson et al 1994, P. olseni from the blacklip abalone Haliotis ruber (Lester & Davis 1981), and clams R. decussatus and R. philippinarum (Azevedo 1989, Navas et al 1992, P. qugwadi from Japanese scallops Patinopecten yessoensis (Blackbourn et al 1998), P. chesapeaki from the clams Mya arenaria and Macoma balthica (McLaughlin & Faisal 1999, Coss et al 2001, Dungan et al 2002, P. mediterraneus from the European flat oyster Ostrea edulis (Casas et al 2004), P. honshuensis from R. philippinarum (Dungan & Reece 2006) and P. beihaiensis from C. ariakensis (Moss et al 2008).…”